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Al₂O₃ used as gate dielectric enables exploitation of higher electric field capacity of SiC, improving capacitive coupling and memory retention in flash memories. Passivation of traps at interface and in bulk which causes serious threat is necessary for better performance. The purpose of this paper is to investigate the effect of post-deposition rapid thermal annealing (PDA) and post-metallization annealing (PMA) on the structural and electrical characteristics of Pd/Al2O3/6H-SiC capacitors.

Al₂O₃ film is deposited by ALD; PDA is performed by rapid thermal annealing (RTA) in N₂ at 900°C for 1 min and PMA in forming gas for 10 and 40 min. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) measurements data are studied in addition to capacitance-voltage (C-V) and current-voltage (I-V) characteristics for the fabricated Pd/Al₂O₃/SiC capacitors. Conduction mechanism contributing to the gate leakage current is extracted for the entire range of gate electric field.

RTA forms aluminum silicide at the interface causing an increase in the density of the interface states and gate leakage current for devices with an annealed film, when compared with an as-deposited film. One order improvement in leakage current has been observed for the devices with RTA, after subjecting to PMA for 40 min, compared with those devices for which PMA was carried out for 10 min. Whereas, no improvement in leakage current has been observed for the devices on as-deposited film, even after subjecting to PMA for 40 min. Conduction mechanisms contributing to gate leakage current are extracted for the investigated Al₂O₃/SiC capacitors and are found to be trapfilled limit process at low-field regions; trapassisted tunneling in the mid-field regions and Fowler–Nordheim (FN) tunneling are dominating in high-field regions.

The effect of PDA and PMA on the structural and electrical characteristics of Pd/Al₂O₃/SiC capacitors suitable for flash memory applications is investigated in this paper.

Thick film superconductors have been produced by screen printing and annealing pastes made from oxide powders and pre‐annealed powders. These films have been analysed by X‐ray diffraction, microwave absorption, resistance vs. temperature measurements, and adhesion tests. Results show the correlation between structural and electrical properties.

This paper seeks to summarise the results of available research on the use of high velocity oxy‐fuel (HVOF) thermal‐spray technique to provide protection against high temperature corrosion and erosion‐corrosion of materials.

This paper describes one of the recent thermal‐spray processes, namely HVOF thermal‐spray technology and presents a survey of the studies on the use of this technique to provide protection against corrosion and erosion‐corrosion of high temperature alloys, with a special emphasis on boiler steels.

High temperature corrosion and erosion‐corrosion are serious problems observed in steam‐powered electricity generation plants, gas turbines, internal combustion engines, fluidized bed combustors, industrial waste incinerators and recovery boilers in paper and pulp industries. These problems can be prevented by changing the material or altering the environment, or by separating the component surface from the environment. Corrosion prevention by the use of coatings for separating materials from the environment is gaining importance in surface engineering. Amongst various surface modifying techniques, thermal spraying has developed relatively rapidly due to the use of advanced coating formulations and improvements in coating application technology. One of the variants of thermal spraying, namely HVOF has gained popularity in recent times due to its flexibility for in‐situ applications and superior coating properties.

This review covers mainly information that has been reported previously in the open literature, international journals and some well‐known textbooks.

The paper presents a concise summary of information for scientists and academics, planning to start their research work in the area of surface engineering.

This paper fulfils an identified information/resources need and offers practical help to an individual starting out on a career in the area of surface engineering for erosion‐corrosion and wear.

The purpose of this paper is to present a comprehensive review on development and future trends in zinc oxide thin film transistors (ZnO TFTs). This paper presents the development of TFT technology starting from amorphous silicon, poly-Si to ZnO TFTs. This paper also discusses about transport and device modeling of ZnO TFT and provides a comparative analysis with other TFTs on the basis of performance parameters.

It highlights the need of high–k dielectrics for low leakage and low threshold voltage in ZnO TFTs. This paper also explains the effect of grain boundaries, trap densities and threshold voltage shift on the performance of ZnO TFT. Moreover, it also addresses the challenges like requirement of stable p-type ZnO semiconductor for various electronic applications and high value of ZnO mobility to meet growing demand of high-definition light emitting diode TV (HD-LED TV).

This review will motivate the readers to further investigate the conduction mechanism, best alternate for gate-dielectric and the deposition technique optimization for the enhancement of the performance of ZnO TFTs.

This is a literature review. The technological evolution of TFT in general and ZnO TFT in particular is presented in this paper.

The purpose of this paper is to enhance the understanding on the electrodeposition of various lead (Pb)‐free solder alloys, so that new studies can be carried out to solve processing issues.

The paper reviews the available reports on the electrodeposition of tin (Sn)‐based solder systems and identifies the challenges in this area.

Compositional control remains a major challenge in this area, where the achievement of desired composition for binary and ternary alloys is subjected to uncertainties. The use of chelating agents in the bath and optimization of parameters can assist the achievement of near‐desired alloy composition. Acidic plating baths are preferred due to their compatibility with photoresists but oxidation of stannous ions causes poor bath stability. Antioxidants, reducing agents and low oxygen overpotential anodes can suppress the oxidation rate and increase the lifespan of plating baths. Apart from chelating agents and antioxidants, various categories of additives can be added to improve quality of deposits. Surfactants, grain refiners and brighteners are routinely used to obtain smooth, fine‐grained and bright deposits with good thermo‐mechanical properties.

The paper provides information on the key issues in electrodeposition of Pb‐free solder alloys. Possible measures to alleviate the issues are suggested so that the electrodeposition technique can be established for mass production of a wider range of solder alloys.

This study aims to comprehensively investigate the process-structure-property correlation of acrylonitrile butadiene styrene (ABS) parts manufactured by the overheat material extrusion (Mex) method. This study considers the relationships between the tensile and impact strength with temperature profiles, mesostructures and fracture behaviors of the ABS-printed parts.

The overheat printing condition was generated by using the highest possible printing temperature of the Mex printer used in this study together with cooling fan turned off. Temperature profiles of the polymer rasters were measured to characterize the diffusion time of the deposited rasters. Thermogravimetric analysis, differential scanning calorimetry and melt flow index were performed to study the thermal properties of the ABS feedstock. The mesostructures of the printed ABS samples were characterized by using an optical microscope, while their fracture surface was investigated using a field emission scanning electron microscope. The authors performed the tensile and impact tests following ASTM D3039 and D256-10A, respectively.

The use of the overheat Mex printing could offer better raster diffusion with reduced cooling rate and prolonged diffusion time. Consequently, the overheat printed ABS parts possessed a porosity as low as 1.35% with an increase in the weld length formed between the adjacent rasters of up to 62.5%. More importantly, the overheat printed ABS parts exhibited an increase of up to 70%, 84% and 30% in tensile strain at break, tensile toughness and impact strength, respectively, compared to their normal printed counterparts.

This study provides a facile but effective approach to fabricate highly dense and strong polymeric parts printed by Mex method for end-use applications.

This paper aims to investigate the effects of different ultrasonic-assisted loading degrees on the microstructure, mechanical properties and the fracture morphology of Cu/Zn+15%SAC0307+15%Cu/Al solder joints.

A new method in which 45 μm Zn particles were mixed with 15% 500 nm Cu particles and 15% 500 nm SAC0307 particles as solders (SACZ) and five different ultrasonic loading degrees were applied for realizing the soldering between Cu and Al at 240 °C and 8 MPa. Then, SEM was used to observe and analyze the soldering seam, interface microstructure and fracture morphology; the structural composition was determined by EDS; the phase of the soldering seam was characterized by XRD; and a PTR-1102 bonding tester was adopted to test the average shear strength.

The results manifest that Al–Zn solid solution is formed on the Al side of the Cu/SACZ/Al joints, while the interface IMC (Cu₅Zn₈) is formed on the Cu side of the Cu/SACZ/Al joints. When single ultrasonic was used in soldering, the interface IMC (Cu₅Zn₈) gradually thickens with the increase of ultrasonic degree. It is observed that the proportion of Zn or ZnO areas in solders decreases, and the proportion of Cu–Zn compound areas increases with the variation of ultrasonic degree. The maximum shear strength of joint reaches 46.01 MPa when the dual ultrasonic degree is 60°. The fracture position of the joint gradually shifts from the Al side interface to the solders and then to the Cu side interface.

The mechanism of ultrasonic action on micro-nanoparticles is further studied. By using different ultrasonic loading degrees to realize Cu/Al soldering, it is believed that the understandings gained in this study may offer some new insights for the development of low-temperature soldering methodology for heterogeneous materials.